Water therapy is becoming an increasingly popular alternative in the field of physical therapy for providing a low-impact and yet effective form of exercising without the harmful effects typically associated with more rigorous activities such as running or jogging. In the treatment of rheumatoid arthritis, for example, water therapy has been used to build endurance and strength, ease stiff joints, and relax sore muscles. As water buoyancy tends to greatly reduce the pressure exerted on joints and muscles, such techniques have also been successfully used to treat other medical conditions such as fibromyalgia or polymyalgia rheumatica (PMR), making it easier for individuals suffering from such conditions to perform a needed range of motion exercise. While water therapy is particularly popular as a means of exercise for the disabled and/or for individuals suffering from certain medical conditions, such therapeutic techniques are equally applicable as a form of aquatic exercise for the general public, and may serve other purposes such as recreation, meditation, and/or closeness to God.
In certain types of water therapy such as aquatic exercise or swimming, it is often desirable for the individual's body to float in a face up and horizontal position along the surface of the water, allowing the individual to freely move on the surface of the water without having to exert energy to overcome the effects of gravity. To provide the necessary floatation for water therapy, a personal floatation device (PFD) may be worn to increase the individual's buoyancy within the water. Such personal floatation devices are available in a variety of configurations based on their intended use as well as the size and age of the individual. Other considerations such as heat retention, wetness, and drag may also play a role in the configuration of the personal floatation device.
To differentiate the types of personal floatation devices available, the United States Coast Guard has adopted a classification system rating such devices based on their buoyancy and intended use. A personal floatation device having a “Type I” rating, for example, indicates that the device has over 22 pounds of buoyancy, and is capable of overturning an unconscious individual within the water. A personal floatation device having a “Type III” rating generally indicates a device having a lower buoyancy rating (e.g. 15.5 pounds), often without the ability to overturn an unconscious individual within the water. Because Type I devices are generally designed to maintain the individual in an upright (i.e. face-up) position on the surface of the water, and typically have a greater amount of buoyancy, such devices tend to comprise a life-jacket or vest-type structure whereas Type III devices usually comprise floatation aids that are slipped over the head of the individual. Variations do exist, however.
Despite the many health and recreational benefits associated with water therapy, many conventional personal floatation devices are ill equipped for supporting users in a face up and horizontal position along the surface of the water while also permitting significant freedom of movement. As many personal floatation devices are designed to support the user in a vertical orientation (i.e. with the head up and feet down), such devices are not useful in those water therapy applications where a horizontal orientation is desired. Of those devices capable of orienting the user in both a face up and horizontal position along the surface of the water, such devices tend to be cumbersome to don and wear, making such devices unsuitable for use by certain individuals such as the disabled or elderly. In some cases, the personal floatation device may not adequately compensate for the individual's lower center of gravity, preventing the individual from fully floating on the surface of the water in a stable manner. Furthermore, and in other cases, the personal floatation device may lack the ability to automatically orient the individual in a particular direction within a moving body of water, forcing the individual to exert energy to maintain their bearing within the water.